The present application relates generally to an improved magnetic structure for an interleaved transformer/inductor.
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors or coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer and thus a varying magnetic field through a second or secondary winding. This varying magnetic field induces a varying electromotive force (EMF), or “voltage,” in the secondary winding. This effect is referred to as inductive coupling. Transformers range in size from on-chip transformers occupying the area less than one square millimeter to huge units weighing hundreds of tons used to interconnect portions of power grids.
An inductor is a passive two-terminal electrical component that resists changes in electric current passing through it. An inductor comprises a conductor such as a wire, usually wound into a coil. When a current flows through an inductor, energy is stored temporarily in a magnetic field in the coil. When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, according to Faraday's law of electromagnetic induction, which opposes the change in current that created it.
However, regardless of size, all transformers operate on the same basic principles and, although the range of transformer designs is wide, currently existing structured transformers, when coupled together with inductor flux, exhibit issues, such as magnetic saturation, noise/ripple voltage, and/or poor efficiency.